Stabilization of biocidal activity in air drying alkyds

ABSTRACT

This invention is directed towards stabilizing the biocidal activity of an alkyd composition containing a halopropargyl compound and a transition metal drier by use of a chelating agent.

CROSS REFERENCE

This application is a divisional of U.S. patent application Ser. No.08/752,380 filed Nov. 20, 1996 now patented.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention is directed to alkyd compositions containing ahaloalkynyl biocidal compound, and especially a halopropargyl compound,and a transition metal drier. The invention is particularly directed tosuch compositions which have been stabilized to reduce the loss ofbiocidal activity. The invention is especially directed to thestabilization of alkyd compositions containing iodopropargyl carbamates,such as 3-iodo-2-propargylbutyl carbamate, and a cobalt drier by use ofa chelating agent.

2. Description of Related Art

Both exterior and interior surfaces and substrates of all types, whenexposed to common environmental conditions, e.g. moisture, are prone toattack, discoloration and various kinds of destruction by a variety ofspecies of microorganisms, including fungi, algae, bacteria andprotozoa. As a result, there has always been a great need for aneffective and economical means to protect, for extended periods of time,both exterior and interior surfaces and various type substrates andcommercial formulations from the deterioration and destruction caused bysuch microorganisms.

Materials which need protection with a suitable antimicrobialcomposition include stucco, concrete, stone, cementaceous surfaces,wood, caulking, sealants, leather, plastics, textiles, biodegradablecompositions including such materials as paints and other coatingformulations, surfactants, proteins, starch-based compositions, inks,emulsions and resins as well as numerous other materials and othersubstances which may be attacked by destructive microbes.

Wooden objects, in particular, are subject to degradation from a widevariety of natural pests, principally insects, such as carpenter ants,powder-post beetles and termites, marine borers and fungi. Fungi areparticularly prevalent and are divided into three main groups, the brownrots, white rots and soft rots. Fortunately, a variety of compositionshave been developed for treating wooden objects to retard thedestructive effect of such pests.

An enormously wide variety of materials have been identified which, tovarious degrees, are effective in retarding or preventing the growth of,and accompanying destruction caused by, such microbes. Such biocidalcompounds include halogenated compounds, organometallic compounds,quaternary ammonium compounds, phenolics, metallic salts, heterocyclicamines, formaldehyde donors, organo-sulfur compounds and the like.

One of the most common ways to apply such materials to wooden objects isto include them in a composition used to coat the object. The coating,in the form of paints, lacquers and varnishes, functions as a vehiclefor the biocidal agent and acts as a barrier to the natural elements,such as sunlight and precipitation. A widely used coating formulationcontains an alkyd resin, an oil, an optional solvent thinner and adrier. Such compositions form dried film coatings by a combination ofsolvent evaporation, resin oxidation and polymerization. The process isaccelerated by the drier, which typically is a transition metalcompound. Cobalt is the most widely used of the transition metals insuch driers. To obtain a more uniform hardening, the cobalt drier isoften combined with a lead compound or calcium/zirconium mixture.

One well-known class of biocides used in such coating compositions arethose containing a halopropargyl moiety, and especially an iodopropargylmoiety. Such compounds are widely disclosed in the patent literatureincluding U.S. Pat. Nos. 3,660,499; 3,923,870; 4,259,350; 4,592,773;4,616,004 and 4,639,460 to name a few. Included within this class ofcompounds are the halopropargyl carbamates which are known primarily fortheir fungicidal activity. 3-iodo-2-propargyl butyl carbamate,hereinafter also referred to as IPBC, is one of the best known andprobably the most widely used of the halopropargyl carbamate fungicides.IPBC is a highly active broad spectrum fungicide. In addition to itsfungicidal activity, IPBC also has been associated with algaecidalactivity. In this regard, Great Britain Patent 2,138,292 and U.S. Pat.Nos. 4,915,909 and 5,082,722 contain such disclosures.

Haloalkynyl compounds, including halopropargyl compounds, and especiallythe halopropargyl carbamates, are formulated with a variety of otheringredients in both aqueous and organic solvent mixtures to form coatingmaterials. For various reasons, it is desired that these coatingcompositions maintain their biocidal activity for prolonged periods oftime. Unfortunately, alkyd coating compositions containing transitionmetal driers have sometimes been observed to experience a progressiveloss in such activity.

In particular, applicants have found that the gradual loss of biocidalactivity in such alkyd coating formulations discussed above is caused bya reaction between the transition metal drier in these compositions andthe haloalkynyl compounds.

Applicants have discovered that adding a chelating agent to such alkydcompositions formulated with a transition metal drier, particularly acobalt drier, and a biocidal haloalkynyl compound, includingspecifically halopropargyl compounds such as IPBC, significantly retardsthe degradation of the biocidal agent. Use of the invention also helpsto ameliorate other problems, such as the formation of lacrimators andthe corrosion of metal containers caused by degradation of IPBC insolvent-based alkyd paint formulations.

BRIEF DESCRIPTION OF THE INVENTION

The present invention is based, therefore, on the discovery of acomposition and method for stabilizing the biocidal activity of certainalkyd formulations containing a haloalkynyl compound and a transitionmetal drier, particularly a cobalt drier. The invention is specificallydirected to alkyd compositions and method for stabilizing the biocidalactivity of a halopropargyl compound, and particularly a halopropargylcarbamate fungicide, in such compositions against a decline in biocidalactivity due to the presence of a cobalt drier. The present inventionstabilizes the biocidal activity of an alkyd composition containing ahalopropargyl compound and a cobalt transition metal drier through theaddition of a chelating agent, wherein the mole ratio of said cobalttransition metal drier and said chelating agent is between 1:1 to 1:8.

The present invention also provides a method for stabilizing an alkydformulation containing a halopropargyl compound, said formulationcontaining an amount of a transition metal drier sufficient to causedegradation of said halopropargyl compound, which comprises adding asufficient amount of a chelating agent to said formulation to retardreaction between the transition metal drier and the halopropargylcompound.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 graphically presents the stability of IPBC in the formulations ofExamples 1 through 5.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is directed to an alkyd composition and a methodfor stabilizing alkyd formulations containing a haloalkynyl compound anda transition metal drier, particularly a cobalt drier. The invention isspecifically directed to an alkyd composition and a method for reducingthe degradation of halopropargyl compounds, particularly a halopropargylcarbamate such as IPBC, in aqueous- or organic solvent-based alkydformulations, caused by the presence of a degradation-causing amount ofa cobalt transition metal drier. The invention thus provides forstabilized alkyd compositions containing a biocidal halopropargylcompound and a cobalt transition metal drier.

Alkyd resins used for preparing the compositions of the presentinvention are those resins widely known to those skilled in the art.Such resins are thermosetting polymers similar to polyester resins andtypically comprise the condensation product of a polybasic acid, such asphthalic anhydride, and a polyhydric alcohol, such as ethylene glycol,glycerol or pentaerythritol, usually with a drying oil modifier. Thepresent invention is not to be limited to any particular class of alkydsand is broadly applicable to any alkyd-type resin which utilizes atransition metal compound to accelerate resin film formation and drying.

Typical driers used in the industry for accelerating the drying orhardening of oxidizable alkyd coatings include transition metals such ascobalt or combinations of transition metals with other non-transitionmetals such as a combination of cobalt and either lead orcalcium/zirconium. Other transition metals that can be used foraccelerating the drying of alkyd compositions can be found in groups IB,VIIB and VIII of the periodic table of the elements. While not all ofthese metals have as strong an adverse impact on the stability ofhaloalkynyl biocides as does cobalt, the present invention provides acomposition and method for ameliorating any degradation caused by theirinteraction. Since cobalt has been observed to cause the most drasticloss in activity of the haloalkynyl biocides, and particularly IPBC, andit also happens to be the drier used most widely commercially, thepresent invention will be described principally in that context. Thoseskilled in the art will recognized the applicability and adaptability ofthe following disclosure to alkyd formulations containing othertransition metal driers, however.

The transition metal driers generally comprise an oil-soluble salt ofthe transition metal, and often a fatty acid salt. Common transitionmetal driers are cobalt octoate and cobalt naphthenate. Applicants havediscovered that transition metals react with halopropargyl compounds andcause degradation of the biocidal compounds. The degradation of theactive halopropargyl compound results in a loss of biocidal activity inalkyd formulation containing a transition metal drier.

A halopropargyl compound for use in the present invention can beidentified by the following structure:

    YC.tbd.C--CH.sub.2 X

wherein Y is a halogen, preferably iodine and X can be (1) oxygen whichis part of an organic functional group; (2) nitrogen which is part of anorganic functional group; (3) sulfur which is part of an organicfunctional group; or (4) carbon which is part of an organic functionalgroup.

The functional group of which oxygen is a part is preferably an ether,ester, or carbamate group. The functional group of which nitrogen is apart is preferably an amine, amide, urea, nitrile, or carbamate group.The functional group of which sulfur is a part is preferably a thiol,thiane, sulfone, or sulfoxide group. The organic functional group ofwhich carbon is a part is preferably an ester, carbamate or alkyl group.

Examples of compounds which may be used as the halopropargyl compound ofthis invention are especially the fungicidally active iodopropargylderivatives. In this regard, please see U.S. Pat. Nos. 3,923,870,4,259,350, 4,592,773, 4,616,004, 4,719,227, and 4,945,109, thedisclosures of which are herein incorporated by reference. Theseiodopropargyl derivatives include compounds derived from propargyl oriodopropargyl alcohols such as the esters, ethers, acetals, carbamatesand carbonates and the iodopropargyl derivatives of pyrimidines,thiazolinones, tetrazoles, triazinones, sulfamides, benzothiazoles,ammonium salts, carboxamides, hydroxamates, and ureas. Preferred amongthese compounds is the halopropargyl carbamate, 3-iodo-2-propynyl butylcarbamate (IPBC). This compound is included within the broadly usefulclass of compounds having the generic formula: ##STR1##

Wherein R is selected from the group consisting of hydrogen, substitutedand unsubstituted alkyl groups having from 1 to 20 carbon atoms,substituted and unsubstituted aryl, alkylaryl, and aralkyl groups havingfrom 6 to 20 carbon atoms and from substituted and unsubstitutedcycloalkyl and cycloalkenyl groups of 3 to 10 carbon atoms, and m and nare independently integers from 1 to 3, i.e., m and n are notnecessarily the same.

Particularly preferred are formulations of such halopropargyl carbamateswhere m is 1 and n is 1 having the following formula: ##STR2##

Suitable R substituents include alkyls such as methyl, ethyl, propyl,n-butyl, t-butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, dodecyl,octadecyl, cycloalkyls such as cyclohexyl, aryls, alkaryls and aralkylssuch as phenyl, benzyl, tolyl, cumyl, halogenated alkyls and aryls, suchas chlorobutryl and chlorophenyl, and alkoxy aryls such as ethoxyphenyland the like.

Especially preferred are such iodopropargyl carbamates as3-iodo-2-propynyl propyl carbamate, 3-iodo-2-propynyl butyl carbamate,3-iodo-2-propynyl hexyl carbamate, 3-iodo-2-propynyl cyclohexylcarbamate, 3-iodo-2-propynyl phenyl carbamate, and mixtures thereof.

The amount of the halopropargyl compound and cobalt transition metaldrier in alkyd formulations which are stabilized in accordance with thepresent invention can vary widely and an optimum amount generally isaffected by the intended application and other components of aparticular formulation. In any event, generally such alkyd formulationscontain anywhere from about 0.05 to about 1.0 percent by weight of suchhalopropargyl compound and from about 0.005 to about 0.15 percent byweight of such cobalt transition metal drier. Usually, such alkydformulations contain from 0.1 to 0.6 percent by weight of suchhalopropargyl compound and from 0.01 to 0.06 percent by weight of suchcobalt transition metal drier. Such alkyd formulations, protectedagainst microbial attack by the inclusion of a halopropargyl carbamate,can be prepared from highly concentrated compositions of thehalopropargyl active ingredients, such as by appropriate dilution.Oftentimes, the optimum range of the halopropargyl carbamate is about0.05% to 1.0%.

Alkyd compositions of the present invention will generally be formulatedby mixing the halopropargyl active ingredient or a concentrate of thehalopropargyl compound, in the liquid vehicle for the alkyd resin fordissolving or suspending the active component. As noted, the compositionalso will be provided with one or more transition metals as adjuvantswhich are conventionally employed as driers in the compositions.

The key constituent of the present invention is a chelating agent forenhancing the stability of the haloalkynyl biocide in the alkydcomposition containing a transition metal drier. Any compound havingligands which can form coordinate bonds with a transition metal ispotentially useful as a chelating agent in the present invention.

Suitable chelating agents which can be used to stabilize alkydcompositions containing a halopropargyl compound and transition metaldrier thus include, but are not limited to, ethylenediaminetetraaceticacid (EDTA), ethylenediamine, acetylacetone, nitrilotriacetic acid,ethylene glycol-bis(β-aminoethyl ether)-N,N-tetraacetic acid,2,2'-bipyridine, 1,10-phenanthroline, substituted ethylenediamine (bothon nitrogen and carbon e.g. N,N,N', N'-tetramethyl ethylenediamine),2-and 8-hydroxyquinoline and their substituted derivatives e.g.8-hydroxyquinaldine, 2-hydroxy-4-methylquinaldine,5-chloro-8-hydroxyquinoline, 5,7-dichloro-8-hydroxyquinoline,2,4-quinolinediol; 2- and 8-quinolinethiol and its derivatives;8-aminoquinoline and its derivatives; substituted 2,2'-bipyridine e.g.4,4'-dimethyl-2,2'-dipyridyl, 2,2':6',2"-terpyridine,4,4'-diphenyl-2,2'-dipyridyl, 2,2'-dipyridine-3,3'-diol; substituted1,10-phenanthroline derivatives e.g. 4-methyl-1,10-phenanthroline,5-methyl-1,10-phenanthroline, 4,7-dimethyl-1,10-phenanthroline,5,6-dimethyl-1,10-phenanthroline,3,4,7,8-tetramethyl-1,10-phenanthroline,4,7-diphenyl-1,10-phenanthroline, 2,9-dimethyl-4,7-dimethyl-1,10-phenanthroline; 2,2'-biquinoline; 2-quinoxalinol;3-methyl-2-quinoxalinol; 2,3-dihydroxyquinoxaline; 2-mercaptopyridine;2-dimethylaminopyridine; 1,2-bis(dimethylphosphino)ethane;1,2-bis(diethylphosphino) ethane; 1,2-bis(diphenylphosphino) ethane;1,3-bis(diphenylphosphino) propane; and 1,4-bis(diphenylphosphino)butane.

According to the invention a sufficient amount of chelating agent isadded to the halopropargyl compound and cobalt transition metal driercontaining alkyd composition to inhibit the loss of biocidal activity ofthe alkyd formulation. A sufficient amount of chelating agent is anamount effective to inhibit or retard the degradation of thehalopropargyl compound in the alkyd formulation. The amount of chelatingagent added should be sufficient to stabilize the halopropargyl compoundas well as not significantly interfere with the drier activity of thetransition metal compound for the specific application of the end-useformulation. An amount of chelating agent can be determined by routinetesting of the stability of the halopropargyl compound in the presenceof the transition metal in the alkyd formulation with varying amounts ofadded chelating agent. Methods for assaying stability of thehalopropargyl compound are known and available to one skilled in theart. The amount of chelating agent needed in a particular alkydcomposition is related to the amount of transition metal drier presentin the formulation. Usually a sufficient amount of chelating agent willbe from about 1 to about 8 moles of chelating agent per mole transitionmetal drier in the formulation. More preferably, the mole ratio of thechelating agent and the transition metal drier is from about 1:1 toabout 6:1.

Compositions of the present invention may also include a liquid vehicle,such as for solubilizing the haloalkynyl biocide and/or reducing theviscosity of the formulation. Useful liquid vehicles, including organicsolvents for the halopropynyl compound, particularly the preferrediodopropynyl butyl carbamate, are water, alcohols, such as methanol,butanol and octanol, glycols, several glycol ethers like propyleneglycol n-butyl ether, propylene glycol tert-butyl ether,2-(2-methoxymethylethoxy)-tripropylene glycol methyl ether, propyleneglycol methyl ether, dipropyleneglycol methyl ether, tripropyleneleneglycol methyl ether, propylene glycol n-butyl ether and the esters ofthe previously mentioned compounds. Other useful solvents are n-methylpyrrolidone, n-pentyl propionate, 1-methoxy-2-propanol, dibasic estersof several dicarboxylic acids and mixtures thereof, such as the dibasicisobutyl ester blend of succinic, glutaric and adipic acids, aromatichydrocarbons, such as xylene and toluene, high aromatic petroleumdistillates, e.g., solvent naphtha, distilled tar oil, mineral oils,ketones such as acetone, and petroleum fractions such as mineral spiritsand kerosene. Other suitable organic solvents are well known to thoseskilled in the art.

When preparing alkyd formulations of the present invention for specificapplications, the composition also will likely be provided with otheradjuvants conventionally employed in compositions intended for suchapplications such as additional fungicides, auxiliary solvents,processing additives, plasticizers, UV-stabilizers or stabilityenhancers, water soluble or water insoluble dyes, color pigments,corrosion inhibitors, anti-settlement agents, anti-skinning agents andthe like. Additional fungicides used in the composition are preferablysoluble in the liquid vehicle.

As noted above, the chelating agent is added to an alkyd formulationcontaining a halopropargyl compound and a transition metal drier. In theabsence of such chelating additive, the halopropargyl compound and thetransition metal drier would react with each other and cause a prematuredegradation of the biocidal activity of the halopropargyl compound. Thechelating agent is added in a sufficient amount to counteract anyreaction between the halopropargyl compound and the transition metal.

A particularly preferred aspect of the present invention relates to acomposition containing a halopropargyl compound and a chelating agent,as described above, which can be sold as a concentrate and which isuseful as the biocidal additive for introducing the halopropargylcompound, and especially IPBC, into end-use alkyd formulationscontaining one or more transition metal driers for providing a stablebiocidal activity. Generally, such a concentrate comprises a mixture ofthe halopropargyl compound and a chelating agent in a weight ratio ofhalopropargyl compound to a chelating agent in the range of 1:1 to 8:1.Such a concentrate is useful for imparting biocidal activity to theend-use alkyd formulation. Throughout the specification and claims, theterm "end-use formulation" is intended to embrace the wide variety offormulations which have used halopropargyl compounds for impartingbiocidal activity including paints, stains and other alkyd-basedcoatings.

The following examples are presented to illustrate and explain theinvention. Unless otherwise indicated, all references to parts andpercentages here and throughout the application are based on weight.

EXAMPLES

Examples 1-5 demonstrate the degradation of haloalkynyl compounds causedby co-ordination of transition metals to the alkyne. In particular, thestability of 3-iodo-2-propynyl butylcarbamate (IPBC) in a solvent ofDowanol PnB (Dow Chemical Corporation) was examined as this solvent iswidely used in the paints and coatings industry and provides thesolubility of IPBC and the transition metal driers commonly used. Thedriers chosen for this investigation were the calcium, manganese, cobaltand zirconium octoates widely used in the industry. The first exampleserves as a control and illustrates the stability of IPBC in thesolvent, Dowanol PnB. Examples 2-5 illustrate the stability of IPBC inpresence of various transition metal driers. The data demonstrates thedramatic effect that a cobalt drier in particular, has on the stabilityof IPBC. These results are graphically presented in FIG. 1.

Example 1

A 10% solution of IPBC was prepared by dissolving 5.0 g TroysanPolyphase^(R) P100 in 45.0 g Dowanol PnB. The solution was heat aged at45° C. for six weeks and was analyzed for the IPBC content at about oneweek intervals by HPLC. The results are presented in Table 1.

                  TABLE 1    ______________________________________    Stability of IPBC in Dowanol PnB at 45° C.    ______________________________________    Time in Days             0       9      15   23    28    34   42    % IPBC   10      9.9    9.8  9.8   9.9   9.9  9.7    ______________________________________

Example 2

A solution of IPBC was prepared by dissolving 5.0 g TroysanPolyphase^(R) P100 in 44.17 g Dowanol PnB. To this solution was added0.83 g Troymax Manganese^(R) 6% and the resulting solution was aged at45° C. for six weeks and was analyzed for the IPBC content at about oneweek intervals. The results are presented in Table 2.

                  TABLE 2    ______________________________________    Stability of IPBC in the presence of Manganese drier at 45°    ______________________________________    C.    Time in Days             0       9      15   23    28    34   42    % IPBC   10      9.8    9.4  8.6   8.1   7.7  6.9    ______________________________________

Example 3

A solution of IPBC was prepared by dissolving 5.0 g TroysanPolyphase^(R) P100 in 44.17 g Dowanol PnB. To this solution was added0.83 g Troymax Zirconium^(R) 6% and the resulting solution was aged at45° C. for six weeks and was analyzed for the IPBC content at about oneweek intervals. The results are presented in Table 3.

                  TABLE 3    ______________________________________    Stability of IPBC in the presence of Zirconium drier at 45°    ______________________________________    C.    Time in Days             0       9      15   23    28    34   42    % IPBC   10      9.9    9.7  9.6   9.7   9.8  9.6    ______________________________________

Example 4

A solution of IPBC was prepared by dissolving 5.0 g TroysanPolyphase^(R) P100 in 44.17 g Dowanol PnB. To this solution was added0.83 g Troymax Calcium^(R) 6% and the resulting solution was aged at 45°C. for six weeks and was analyzed for the IPBC content at about one weekintervals. The results are presented in Table 4.

                  TABLE 4    ______________________________________    Stability of IPBC in the presence of Calcium drier at 45° C.    ______________________________________    Time in Days             0       9      15   23    28    34   42    % IPBC   10      9.9    9.7  9.6   9.7   9.8  9.7    ______________________________________

Example 5

A solution of IPBC was prepared by dissolving 5.0 g TroysanPolyphase^(R) P100 in 44.17 g Dowanol PnB. To this solution was added0.83 g Troymax Cobalt^(R) 6% and the resulting solution was aged at 45°C. for six weeks and was analyzed for the IPBC content at about one weekintervals. The results are presented in Table 5.

                  TABLE 5    ______________________________________    Stability of IPBC in the presence of Cobalt drier at 45° C.    ______________________________________    Time in Days             0       9      15   23    28    34   42    % IPBC   10      6.4    4.5  2.6   1.7   1.6  0.4    ______________________________________

Example 6

In this example, the stability of IPBC was evaluated in several alkydformulations with a cobalt drier (Recipe B) and without a cobalt driver(Recipe A). The results clearly indicate that the stability of IPBC isstrongly influenced by the presence of cobalt metal.

A series of alkyd compositions were prepared by using the followinggeneral recipe A:

Recipe A

    ______________________________________    Alkyd Resin       60.0%    IPBC              0.5%    Dowanol PnB       1.3%    Methylethylketoxime                      0.2%    Mineral Spirits   38.0%    ______________________________________

A series of alkyd compositions were prepared by using the followinggeneral recipe B:

Recipe B

    ______________________________________    Alkyd Resin       60.0%    IPBC              0.5%    Dowanol PnB       1.3%    Methylethylketoxime                      0.2%    Mineral Spirits   37.5%    Cobalt Drier 6%   0.5%    ______________________________________

The alkyds prepared as above were heat aged at 45° C. for four weeks andanalyzed for residual IPBC by HPLC at one week intervals. The resultsare presented in Table 6.

                  TABLE 6    ______________________________________    Stability of IPBC at 45° C. in various alkyd formulations.             Residual % IPBC    Alkyd Resin               Initial                      1 Week  2 Weeks                                     3 Weeks                                            4 Weeks    ______________________________________    Recipe A    Cargill 50-5070               0.55   0.52    0.5    0.47   0.47    Duramac 2033               0.5    0.55    0.5    0.51   0.51    Drisoy G-1 0.5    0.53    0.5    0.51   0.51    Admerol 75-M-70               0.53   0.49    0.51   0.5    0.5    Finnresin TA 8200               0.48   0.49    0.45   0.48   0.49    Recipe B    Cargill 50-5070               0.56   0.02    ND.sup.1                                     ND     ND    Duramac 2033               0.5    0.02    ND     ND     ND    Drisoy G-1 0.54   0.06    ND     ND     ND    Amerol 75-M-70               0.5    ND      ND     ND     ND    Finnresin TA 8200               0.67   0.04    ND     ND     ND    ______________________________________     .sup.1 None detected

Example 7

This example demonstrates that using a chelating agent, in particular,1,10-phenanthroline and 2,2'-bipyridine, which form coordinate bondsspecifically with cobalt, substantially improves the stability of IPBCin various alkyd formulations.

A series of alkyd compositions without a chelating agent were preparedaccording to the recipe C as follows:

Recipe C

    ______________________________________    Alkyd Resin (100% solids basis)                        40.0%    Troysan Polyphase.sup.R P100                        0.5%    Methylethylketoxime 0.2%    Troymax Cobalt, 6%  0.27%    Troymax Zirconium, 12%                        0.83%    Mineral spirits     58.2%    ______________________________________

A series of alkyd compositions with a chelating agent were preparedaccording to the recipe D as follows:

Recipe D

    ______________________________________    Alkyd Resin (100% solids basis)                        40.0%    Troysan Polyphase.sup.R P100                        0.5%    Methylethylketoxime 0.2%    Troymax Cobalt, 6%  0.27%    Troymax Zirconium, 12%                        0.83%    Mineral spirits     58.135%    2,2'-Bipyridine     0.065%    ______________________________________

A series of alkyd compositions with a chelating agent were preparedaccording to the recipe E as follows:

Recipe E

    ______________________________________    Alkyd Resin (100% solids basis)                        40.0%    Troysat Polyphase.sup.R P100                        0.5%    Methylethyketoxime  0.2%    Troymax Cobalt, 6%  0.27%    Troymax Zirconium, 12%                        0.83%    Mineral spirits     58.122%    1,10-Phenanthroline 0.078%    ______________________________________

The above recipe C, D and E formulations were heat aged at 45° C. andanalyzed at one week intervals for four weeks for the amount of IPBC byHPLC. The results of this stability study are presented in Table 7.

                  TABLE 7    ______________________________________    Stability of IPBC in various alkyds.             Residual % IPBC    Alkyd Resin               Initial                      1 Week  2.5 Weeks                                     3 Weeks                                            4 Weeks    ______________________________________    Recipe C    Cargill 50-5070               0.44   0.39    --     --     0.01    Duramac 2033               0.46   0.2     --     --     None                                            Detected    Drisoy G-1 0.36   0.27    None   --     None                              Detected      Detected    Admerol 75-M-70               0.44   0.44    --     --     None                                            Detected    Finnresin TA-8200               0.43   0.26    --     --     0.15    Rion R 737.7               0.42   0.36    --     --     0.1    Recipe D    Drisoy G-1 0.35   0.36    0.34   --     0.3    Finnresin TA-8200               0.42   0.49    0.46   --     0.46    Rion R 737.7               0.5    --      0.45   --     0.49    Recipe E    Cargill 50-5070               0.47   0.46    --     --     0.31    Duramac 2033               0.45   --      0.36   --     0.26    Drisoy G-1 0.35   0.38    0.37   --     0.31    Admerol 75-M-70               0.46   0.46    --     --     0.24    ______________________________________

While certain specific embodiments of the invention have been describedwith particularity herein, it will be recognized that variousmodifications thereof will occur to those skilled in the art and it isto be understood that such modifications and variations are to beincluded within the preview of this application and the spirit and scopeof the appended claims. In particular, chelating agents useful in thepresent invention include any material which can form coordinationcomplexes with transition metals and thus protect alkynes fromdegradation.

We claim:
 1. A biocidal concentrate comprising a mixture of ahalopropargyl compound and a chelating agent, wherein the weight ratioof said halopropargyl compound to said chelating agent is between 1:1 to8:1 and wherein said concentrate is useful for providing biocidalactivity to an alkyd formulation containing a transition metal drier andfor stabilizing the alkyd formulation against degradation of saidhalopropargyl compound.
 2. The biocidal concentrate of claim 1 whereinthe halopropargyl compound is an iodopropargyl derivative selected froman iodopropargyl ester, an iodopropargyl ether, an iodopropargyl acetal,an iodopropargyl carbamate and an iodopropargyl carbonate.
 3. Thebiocidal concentrate of claim 2 wherein the iodopropargyl carbamate hasthe formula: ##STR3## where R is selected from the group consisting ofhydrogen, substituted and unsubstituted alkyl groups having from 1 to 20carbon atoms, substituted and unsubstituted aryl, alkylaryl, and aralkylgroups having from 6 to 20 carbon atoms and from substituted andunsubstituted cycloalkyl and cycloalkenyl groups of 3 to 10 carbonatoms.
 4. The biocidal concentrate of claim 3 wherein the transitionmetal is cobalt.
 5. The biocidal concentrate of claim 4 wherein thechelating agent is selected from the group consisting ofethylenediaminetetraacetic acid, ethylenediamine, acetylacetone,nitrilotriacetic acid, ethyleneglycol-bis(β-aminoethylether)-N,N-tetraacetic acid, 2,2'-bipyridine, 1,10-phenanthroline,N,N,N',N'-tetramethyl ethylenediamine, 2-hydroxyquinoline,8-hydroxyquinoline, 8-hydroxyquinaldine, 2-hydroxy-4-methylquinaldine,5-chloro-8-hydroxyquinoline, 5,7-dichloro-8-hydroxyquinoline,2,4-quinolinediol, 2-quinolinethiol, 8-quinolinethiol, 8-aminoquinoline,4,4'-dimethyl-2,2'-dipyridyl, 2,2':6',2"-terpyridine,4,4'-diphenyl-2,2'-dipyridyl, 2,2"-dipyridine-3,3'-diol,4-methyl-1,10-phenanthroline, 5-methyl-1,10-phenanthroline,4,7-dimethyl-1,10-phenanthroline, 5,6-dimethyl-1,10-phenanthroline,3,4,7,8-tetramethyl-1,10-phenanthroline,4,7-diphenyl-1,10-phenanthroline,2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline, 2,2'-biquinoline,2-quinoxalinol, 3-methyl-2-quinoxalinol, 2,3-dihydroxyquinoxaline,2-mercaptopyridine, 2-dimethylaminopyridine,1,2-bis(dimethylphosphino)ethane, 1,2-bis(diethylphosphino)ethane,1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, and1,4-bis(diphenylphosphino)butane.
 6. The biocidal concentrate of claim 5wherein the iodopropargyl carbamate is selected from the groupconsisting of 3-iodo-2-propynyl propyl carbamate, 3-iodo-2-propynylbutyl carbamate, 3-iodo-2-propynyl hexyl carbamate, 3-iodo-2-propynylcyclohexyl carbamate, 3-iodo-2-propynyl phenyl carbamate, and mixturesthereof.
 7. The biocidal concentrate of claim 6, wherein theiodopropargyl carbamate is 3-iodo-2-propynyl butyl carbamate and thechelating agent is 2,2'-bipyridine.